It’s not that the tracking website isn’t working. The barge is probably out of range of a land base

from marinetraffic.com

Why cannot I see my vessel?
The MarineTraffic system does not cover all the seas of the world, but only specific coastal areas where a land-based AIS receiver is installed. Vessels appearing on the live map are equipped with an operational AIS transponder and they sail within the reception range of an AIS receiver installed on the land. Possible reasons for a vessel’s position not picked up and displayed on the live map are:
– The vessel is not equipped with an AIS transponder or the transponder is not operational or the transponder is not properly working
– The vessel sails in an area where no nearby AIS receiving station exists/> – Th- The transmission power of the vessel’s AIS transponder is not enough in order for a land-based station to receive the signals. This depends on the type of the transponder, the type and the height of the antenna and the quality of the cabling
– Especially for vessels equipped with a Class-B AIS transponder, the transmission power of AIS signals is much lower than the power of a Class-A transponder and therefore the reception range in much more restricted
– The AIS transponder of the vessel is not configured to transmit the correct information (e.g. MMSI number, ship’s name etc.)
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